One of the main goals of the future energy grids is high penetration of Renewable Energy Sources (RES). However, because of their uncontrollable nature, RES integration often causes grid stability problems. Furthermore, from economic and efficiency points of view, local load balancing and consumption within the same microgrid are the most desirable choices for residential renewable energy systems. Hence, achieving sustainable communities that can be decoupled from the main grid is one of the final aims of decentralized energy grids powered by Distributed Energy Resources (DER).
With high penetration of RES, the issues related to discrepancy in demand and generation can become much more severe than what can be managed through reasonably sized electricity storage. For instance, in Germany there are already grid segments in which, during peak sunshine hours, the electricity flows at a high rate to higher voltage levels since the local demand is much lower. Such a significant difference in demand and supply could not be completely mitigated through electricity storage that can be normally found in the residential sector.
On the other hand, many households feature a different type of energy storage that can be used to improve the balancing performance. Namely, many households have thermal storage used for heating and domestic hot water. Furthermore, electric boilers and heat pumps are also available in many households, providing a coupling point between two energy carriers: electricity and heat. Similarly to heat demand, the electricity to thermal coupling points can represent cooling units. Hence, in the following text all references to heating can be equally applied to the cooling.